Impact of reacting pressure on Na thermal transformation in two full‐scale devices using Zhundong coal at similar temperature

Abstract Gasification and combustion are two common methods for Zhundong (ZD) coal utilization. In the present study, it was intended to investigate thermal transformation of Na in ZD at Lurgi fixed bed gasifier (Lurgi) circulating fluidized boiler (CFBB). To this end, raw samples before gasification gasified slags were gathered from Lurgi, combustion, burned slag, fly ash collected CFBB. The occurrence form analyzed by extraction experiments, inductively coupled plasma‐optical emission spectrometry (ICP‐OES), X‐ray diffraction (XRD), scanning electron microscopy (SEM). obtained results revealed that insoluble slag exceeded 90% under high‐pressure process. It found high temperatures intensify conversion sodium 2 Ca 3 Si O 8 NaAlSiO 4 . performed analyses content CFBB above 92%, SiO NaAlSi main minerals solid residue. 76.64% initial migrated into after process, which 7.05% higher than sum combustion. During CFBB, pressures significantly reduce release gaseous so more retained slag.